PNA is a DNA mimic, in which the entire negatively-charged sugar phosphate backbone is replaced with a neutral one consisting of repeated N-(2-aminoethyl) glycine units linked by peptide bonds. It is stable chemically and biologically.
Nucleic acid testing is highly specific and often provides definitive identification of a disease or pathogen. Methods to detect nucleic acid sequences are dominated by PCR, but applying PCR-based techniques outside of a modern laboratory is challenging. Samples collected in the field, for instance, typically contain inhibitors of the polymerases used in PCR amplification. These inhibitors can be naturally occurring (such as humic acids, urea, heme, Ca2+, proteinases, and/or polysaccharides) or come from items used to collect the samples (namely glove powder, NaCl, KCl, EDTA, SDS, and phenol). These inhibitors can be difficult to remove from samples in the field. While there are other non-PCR-based detection platforms for nucleic acid analysis, they are similarly limited to a laboratory environment.